Witold Malinowski

Publications of Witold Malinowski

• Reasons for giving up breastfeeding and support during problems with lactation in the north-western part of Poland.

  Authors: Dorota Cwiek, Dorota Branecka-Woźniak, Dorota Fryc, Elzbieta Grochans, Witold Malinowski

  Annales Academiae Medicae Stetinensis. 01/2010; 56(2):129-32.

  Breastfeeding is the optimal way of feeding for neonates and infants. Its duration is of vital importance for the child's development and health. The World Health Organization recommends exclusiveBreastfeeding is the optimal way of feeding for neonates and infants. Its duration is of vital importance for the child's development and health. The World Health Organization recommends exclusive breastfeeding until the end of the sixth month of life. Many mothers give up breastfeeding earlier than recommended. Professional and non-professional support plays a great role in motivation to start and continue breastfeeding. The aim of this study was to determine how long infants from Szczecin, the capital city of the North-Western region of Poland, are breastfed, what are the reasons for giving up breastfeeding, and whether mothers obtain support in case of problems with lactation. One hundred randomly chosen mothers with children aged 12-18 months, living in Szczecin, were examined. A questionnaire was administered to the mothers during a direct interview. Prior to the interview, consent of the mothers to participate in the study was obtained. More than 8% of the mothers gave up breastfeeding during the first month after delivery, 68% were breastfeeding till the end of the third month, 31.5% were breastfeeding till the end of the sixth month, and only 2% continued to breastfeed for one year or longer. The most frequent reasons for giving up breastfeeding were: return to work (43.4%), small volume of milk (29.3%) and child's reluctance to suck (18.5%). 62% of breastfeeding women benefited from support during lactation problems but only 6% visited an outpatient breastfeeding service or joined a breastfeeding mothers support group. Support was obtained from the family midwife (37%), pediatrician (32%), and midwife at an outpatient clinic (25.8%). Most women (74.2%) were satisfied with the support. (1) It is necessary to promote breastfeeding so that all women could decide to start breastfeeding after childbirth. 2. As the percentage of women who continue breastfeeding after the sixth month of the infant's life is unsatisfactory, mothers should be encouraged to breastfeed longer. (3) A system of professional lactation support for breastfeeding mothers should be developed.

• [Birth status and twin birth weight discordance]

  Authors: Sławomir Szymański, Witold Malinowski, Elzbieta Ronin-Walknowska

  Ginekologia polska. 09/2009; 80(9):664-9.

  OBJECTIVES: The aim of the research was to estimate the influence of birth weight discordance on birth status of twins. MATERIAL AND METHODS: Material of the research consisted of 560 foetusesOBJECTIVES: The aim of the research was to estimate the influence of birth weight discordance on birth status of twins. MATERIAL AND METHODS: Material of the research consisted of 560 foetuses derived from successful twin pregnancies. In the analysis the following factors were taken into consideration: birth status, gasometry, and birth weight discordance. RESULTS: The degree of birth weight discordance under 10% was noted in 50% of twin pregnancies (n = 140), discordance of 10%-20% was observed in 30.7% (n = 86), and > 20% - in 19.3% (n = 54). CONCLUSIONS: Birth weight discordance is an important risk factor for fetal and neonatal morbidity which is higher in smaller twins than in larger ones. Along with the degree of birth weight discordance, an increased risk of neonatal complications was observed.

• [Women's opinions regarding gynaecological examination in a hospital]

  Authors: Katarzyna Szymoniak, Dorota Cwiek, Elwira Berezowska, Dorota Branecka-Woźniak, Iwona Dzióbek, Witold Malinowski

  Ginekologia polska. 08/2009; 80(7):498-502.

  A visit to the gynaecologist is connected with considerable embarrassment and stress for most women. AIM OF THE RESEARCH: To ascertain patients' opinions about gynaecological examination, frequencyA visit to the gynaecologist is connected with considerable embarrassment and stress for most women. AIM OF THE RESEARCH: To ascertain patients' opinions about gynaecological examination, frequency of visits, and doctors' attitudes towards patients. MATERIAL AND METHODS: A hundred women from Western-Pomeranian region underwent an anonymous examination. The women were divided into three age groups: 20-40, 41-60 and 61+. The study was carried out in two hospital clinics of the Pomeranian Medical University: the Clinic of Procreation and Gynaecology and the Clinic of Obstetric and Gynaecology, between 2006-2007. RESULTS: 70% of the respondents find the gynaecological examination embarrassing and stressful. According to patients, the most unpleasant moment during their visit to the gynaecologist is time spent in the gynaecological chair (47%) and preparation for the examination (30%), whereas the least embarrassing moment is the gynaecological examination itself (21%). However, the most embarrassing moment of the examination is vaginal examination (40%), rectal examination (33%), colposcopy (27%), and breast examination (2%). All the women stated that gynaecological examination is necessary; with 40% of them having examinations once every twelve months, 32% once every six months, 9% once every twenty-four months and 19% even more seldom. Sense of safety and psychical comfort during the examination is ensured by the presence of a qualified midwife (46%), presence of another doctor (9%), privacy (only the doctor and the patient are present) (36%). 53% of the respondents stated that the doctor ensures intimacy during the examination and 47% gave negative answer. Analysis of the doctor's gender indicated that 56% women prefer to be examined by a woman, 37% by a man, and 7% find the gender to be of no importance. The respondents would prefer if the doctor were nice, good-tempered and communicative. CONCLUSIONS: (1) Gynaecological examination is embarrassing and stressful for women and that is why patients expect the gynaecologist to ensure intimacy and sense of safety during the examination, as well as a pleasant individual approach to a patient, and presence of a midwife. (2) The most embarrassing moment is climbing to the gynaecological chair and the most unpleasant moment is the vaginal examination. (3) The fact that women go to the gynaecologist so rarely is particularly worrisome.

• [In Process Citation]

  Authors: Ryszard Poreba, Jacek Brazert, Bogdan Chazan, Ryszard Czajka, Krzysztof Czajkowski, Romuald Debski, Krzysztof Drews, Stefan Jaworski, Agata Karowicz-Bilińska, Janusz Kubicki [......] Stanisław Radowicki, Alfred Reroń, Elzbieta Ronin-Walknowska, Zbigniew Słomko, Wiesław Szymański, Mirosław Wielgoś, Jan Wilczyński, Mariusz Zimmer, Edmund Waszyński, Michał Jóźwik

  Ginekologia polska. 06/2008; 79(5):378-84.

• [Superfecundation in etiology of twin pregnancy]

  Authors: Witold Malinowski, Edmund Waszyński

  Ginekologia polska. 11/2006; 77(10):797-803.

  Superfecundation is the fertilisation of two or more ova from the same cycle by sperm from separate acts of sexual intercourse. The term is also sometimes used to refer to the instances of twoSuperfecundation is the fertilisation of two or more ova from the same cycle by sperm from separate acts of sexual intercourse. The term is also sometimes used to refer to the instances of two different males fathering fraternal twins, though this is more accurately known as heteropaternal superfecundation. This therefore leads to the possibility of twins also being half-siblings. This way of formation of multiply pregnancy aroused and it arouses still among doctors on whole world. This problem aroused large interest also among Polish doctors. For example, we found mention of superfecundation in first Polish medical journal, in Primitiae physico-medicae..., given in Leszno in years 1750-1753. Authors introduced relate opinion of superfecundation in aetiology of multiple pregnancies in historical aspect, as early as from Old Testament to present times as well as current state of medical knowledge of such a situation.

• [Monoamnotic twin pregnancy. Multicenter study]

  Authors: Witold Malinowski, Elzbieta Baś-Budecka, Marek Bilar, Piotr Jóźwiak, Ewa Kuś, Elzbieta Ronin-Walknowska

  Ginekologia polska. 02/2006; 77(1):17-25.

  OBJECTIVE: The purpose of this study was to evaluate of perinatal mortality and morbidity of monoamniotic twins. STUDY DESIGN: This was a multicenter retrospective analysis of 26 monoamniotic twinOBJECTIVE: The purpose of this study was to evaluate of perinatal mortality and morbidity of monoamniotic twins. STUDY DESIGN: This was a multicenter retrospective analysis of 26 monoamniotic twin gestations identified between 1985 and 2004 in a 3 perinatal departments. Of these 26 pregnancies, 11 women were admitted electively for inpatient fetal monitoring. Overall mortality rates, the risk of intrauterine fetal death and neonatal mortality and morbidity, pregnancy complications and fetal anomalies were calculated. RESULTS: Monoamniotic twin pregnancies were diagnosed reliably prenatally by ultrasound in 22 women and at delivery in 4 cases. Of the 26 gestations, spontaneous fetal losses before 22 weeks of gestation were 4 cases. The overall loss rate and the perinatal mortality rate were 52% and 19.4%, respectively. Twenty-two women had both twins alive at 24 weeks of gestation; 11 women were admitted electively for inpatient fetal monitoring at 26-27 week of gestation. In this group there were 2 neonatal deaths. No intrauterine fetal death occurred in any hospitalized patient. In our series there were 100% incidence of prematurity, 38,5% of umbilical cord entaglement, 23% of TTTS, 3.6% of TRAP and 9.6% fetal congenital anomalies. CONCLUSION: Monoamniotic twins are at extremly risk of pregnancy complications and fetal loss. These pregnancies can be diagnosed reliably by ultrasound in most cases. Electively admitted women for inpatient fetal monitoring could be improved neonatal survival and decreased perinatal morbidity.

• The case of monochorionic twin gestation complicated by intrauterine demise of one fetus in the first trimester.

  Authors: Witold Malinowski, Robert Koktysz, Pawel Stawerski

  Twin research and human genetics : the official journal of the International Society for Twin Studies. 07/2005; 8(3):262-6.

  The study investigated the clinical and pathomorphological characteristics of monochorionic diamniotic twin gestations complicated by the spontaneous loss of one fetus during the first trimester.The study investigated the clinical and pathomorphological characteristics of monochorionic diamniotic twin gestations complicated by the spontaneous loss of one fetus during the first trimester. Nine monochorionic diamniotic twin gestations were analyzed in which the demise of one fetus occurred during the first trimester. During the course of the study, 178 twin gestations were sonographically identified during the first trimester. Forty-three (24.2%) were complicated by the intrauterine demise of one fetus before the end of the 12th week of pregnancy. Nine cases were monochorionic diamniotic. The gestational age of the demised fetuses ranged between 5 and 11 weeks (mean 7.4 weeks). The prognoses for the surviving fetuses were rather poor with the surviving co-twin dying 1 to 3 weeks after the first twin, with abortion of both fetuses. In only one case was gestation concluded on the 40th week with delivery of a live neonate. No blood coagulation changes were observed in the affected pregnant women, and the one live newborn did not reveal any haematological or neurological abnormalities. A postnatal study provided evidence for the history of monochorionic diamniotic placentation in all of the cases. In two cases, probable causes of fetal death were established (congenital malformation, the presence of anastomoses between blood vessels). The obtained results suggest an extremely high risk of mortality for the surviving twin fetus following the co-twin's death in cases of monochorial placentation. The morphological evaluation of placentas and fetal membranes enables the establishment of the type of placenta and, in certain cases, the probable cause of the intrauterine demise of one twin fetus during the first trimester of monochorionic diamniotic twin gestation.

• [Intrauterine death of one fetus during the first trimester of monochorionic diamniotic twin gestation]

  Authors: Witold Malinowski, Robert Koktysz, Paweł Stawerski

  Ginekologia polska. 02/2005; 76(1):54-60.

  OBJECTIVES: The goal of our study was the clinical and pathological characteristics of the monochorionic diamniotic twin gestations complicated by the intrauterine death of one fetus during the firstOBJECTIVES: The goal of our study was the clinical and pathological characteristics of the monochorionic diamniotic twin gestations complicated by the intrauterine death of one fetus during the first trimester. MATERIAL AND METHODS: This study is a prospective review of 9 monochorionic diamniotic twin gestations involving the intrauterine death of one fetus during the first trimester. RESULTS: During the study period 178 twin gestations were identified sonographically during the first trimester. Forty three of them (24,2%) were complicated by the intrauterine death of one fetus before the end of 12th gestation week. Nine cases were monochorionic diamniotic. Gestational age of one fetus demise ranged from 5 to 11 (mean 7,4) weeks. Prognoses for surviving fetus were adverse. In 8 cases there was a death of a second fetus after the period of 1 to 3 weeks, with abortion of both fetuses. Only in one case, the gestation has finished in 40th week by delivery of liveborn infant. Maternal coagulation changes did not occur in those cases. One liveborn infant was without evidence of hematological and neurological abnormalities. The postdelivery examination allowed to establish a presence of monochorionic diamniotic placentation in all cases. In two of them, the probable causes of death were established (developmental defect, presence of anastomoses between blood vessels). CONCLUSION: These results suggest that the risk of mortality for the living twin is very high, after the death of its sibling, in case of monochorionic placentation. Morphological examination of placenta and fetal membranes lets to establish a type of placenta, and in some cases a probable cause of intrauterine death of one twin during the first trimester of monochorionic diamniotic twin gestation.

• [Triplets, quadruplets and more...]

  Authors: Witold Malinowski

  Ginekologia polska. 12/2004; 75(11):892-5.

  Theoretically, a woman could bear unlimited number of fetuses. Practically, the human being on the top of his phylogenetic spread, has chosen the singleton birth as its dominant. The anatomicalTheoretically, a woman could bear unlimited number of fetuses. Practically, the human being on the top of his phylogenetic spread, has chosen the singleton birth as its dominant. The anatomical constitution of the woman let her feed no more than two children at the same time. This were probably the reasons for considering the multiple birth as a nature phenomenon. With the time passing, there was a growing body of legends and misunderstandings, based on exagerated histories on their births. Based on world literature, the super multiple births are analyzed.

• [Monochorionic, diamniotic triplet pregnancy complicated by twin reversed arterial perfusion sequence. Postpartum autopsy of placenta and acardiac fetus]

  Authors: Witold Malinowski, Jarosław Szwalski

  Ginekologia polska. 12/2004; 75(11):863-8.

  The twin reversed-arterial-perfusion sequence (TRAP) is a severe complication of monochorionic twin pregnancies characterized by the hemodynamic dependence of a "recipient" twin from a "pump" twin.The twin reversed-arterial-perfusion sequence (TRAP) is a severe complication of monochorionic twin pregnancies characterized by the hemodynamic dependence of a "recipient" twin from a "pump" twin. The recipient twin exhibits lethal abnormalities including acardia and acephaly. The pump twin has a mortality rate of 50% as a result of high-output heart failure. We present a case of a 24-year-old female, gravida 2, para 2, with monochorionic diamniotic triplet pregnancy. The sonographic examination at 18 weeks' gestation revealed acardiac-acephalus fetus. Reversed arterial perfusion sequence was confirmed with Doppler sonography. Postpartum autopsy examination of placenta and acardiac fetus (acardius anceps) was detailed described.

• [Prognostic value of ultrasonography of the yolk sac in singleton pregnancy]

  Authors: Grzegorz Roman, Witold Malinowski

  Ginekologia polska. 09/2004; 75(8):584-8.

  OBJECTIVES: The aim of the research was evaluation of the clinical usefulness of chosen ultrasonographic morphological parameters of the yolk sac in the first trimester of unifetal pregnancies.OBJECTIVES: The aim of the research was evaluation of the clinical usefulness of chosen ultrasonographic morphological parameters of the yolk sac in the first trimester of unifetal pregnancies. MATERIAL AND METHOD: Analysis has been done on 391 cases of unifetal pregnancies in the first trimester. Parameters of ultrasonographic evaluation: diameter, appearance and size of yolk sac, biometrics and fetal anatomy, confirmation of heart beating. CONCLUSIONS: The yolk sac should be observed in the fifth week or when its biggest size equals to 10 mm in a normal pregnancy. Abnormal morphological appearance of the yolk sac and/or the size over 9 mm suggest serious growth disorders of the fetus or its necrobiosis. The yolk sac, apart from cases of hydatid mole, should be possible to be observed between 5-12 weeks of pregnancy.

• [Umbilical cord complications in twin pregnancies]

  Authors: Witold Malinowski

  Ginekologia polska. 11/2003; 74(10):1208-12.

  OBJECTIVES: The postpartum umbilical cord examination can provide a lot of significant information concerning discordant twin growth or reasons of intrauterine death of one or all the fetuses. TheOBJECTIVES: The postpartum umbilical cord examination can provide a lot of significant information concerning discordant twin growth or reasons of intrauterine death of one or all the fetuses. The aim of this study was the postpartum assessment of umbilical cords in twin pregnancies. MATERIAL AND METHODS: The examination material consisted placentas coming from 110 twin pregnancies. The analysis concerned the assessment of placenta types, the umbilical cords attachment place and also the twins birth weight. RESULTS: Basing on the studies of placentas coming from 110 twin pregnancies 76 (69.0%) dichorionic and 34 (31.0%) monochorionic placentas were found. Among dichorionic, 40 (53%) separated and 36 (47%) fused placentas were observed. Among monochorionic 31 (91%) diamniotic and 3 (9.0%) monoamniotic placentas were present. Abnormal umbilical insertion to placenta was most frequently observed in monochorionic pregnancies: in diamniotic--marginal insertion in 21.2%, velamentous insertion in 15.9%, and in monoamniotic--equally 33.3%. In dichorionic pregnancies, for fused placentas--marginal in 8.7%, velamentous in 9.1%, and for separated--5.6% and 3.1%. CONCLUSIONS: The abnormal umbilical cord insertions to the placenta was most frequently found in monochorionic pregnancies. Among pairs of twin born with body weight discordance, the abnormal umbilical cord insertion was more frequently found in the case of the smaller newborn.

• [Intrauterine death of one twin in the third trimester]

  Authors: Witold Malinowski, Józef Janowski, Jerzy Łokociejewski, Kazimierz Rózewicki, Jan Tomala

  Ginekologia polska. 03/2003; 74(2):135-43.

  OBJECTIVES: The goal of our study was the clinical characteristics of the twin gestations complicated by the intrauterine death of one fetus in the third trimester. MATERIAL AND METHODS: This studyOBJECTIVES: The goal of our study was the clinical characteristics of the twin gestations complicated by the intrauterine death of one fetus in the third trimester. MATERIAL AND METHODS: This study was a multicenter retrospective review of 12 twin gestations complicated by the intrauterine death of one fetus in the third trimester. RESULTS: During the study period there were 295 twin gestations. 12 of them (4.1%) were complicated by the intrauterine death of one fetus in the third trimester. Three cases were monochorionic diamniotic and nine dichorionic. Ones gestational age of one fetus demise ranged from 25 to 37 (mean 30.0) weeks. Delivery was performed between 25 and 38 (mean 32.1) weeks. In monochorionic twin gestation the intrauterine death of one twin occurred earlier in gestation, had a shorter duration between the death and delivery, and delivered earlier in gestation. One liveborn infant with monochorionic and two with dichorionic placentation died in the postnatal period. Maternal coagulation changes did not occur in those cases. All live-born infants were without evidence of hematological abnormalities. CONCLUSION: These results suggest that the risk of morbidity and mortality for the living twin is increased, after the death of its sibling, in case of monochorial placentation.

• [Reliability of sonographic diagnosis of chorionicity and amnionicity in twin pregnancy ]

  Authors: Witold Malinowski

  Ginekologia polska. 10/2002; 73(9):763-70.

  OBJECTIVES: The aim of the study was to compare the reliability of chorionicity determination in twin pregnancy using different ultrasonographic methods as compared with post-partum placentalOBJECTIVES: The aim of the study was to compare the reliability of chorionicity determination in twin pregnancy using different ultrasonographic methods as compared with post-partum placental assessment. STUDY DESIGN: The study included 262 spontaneous twin pregnancies delivered at Kutno Hospital between 1989 and 1996. All twin gestations were diagnosed by sonography by the 28-th week's gestation. The ultrasonographic and pathologic correlation between the chorionic and amniotic type was assessed in this group. RESULTS: The ultrasonographic evaluation of the 262 spontaneous twin gestations demonstrated 181 (69.1%) dichorionic and 81 (30.9%) monochorionic twin pregnancies. Three of monochorionic twins were monoamniotic. In all 262 transvaginal and abdominal ultrasonography correctly predicted the chorionic and amniotic type as determined by the pathologic findings. CONCLUSIONS: Ultrasonography before the 28-th week can accurately determine the chorionic and amniotic type in twin pregnancies. The determination of chorionicity during the first half of pregnancy should be based on the various signs. In the second half of pregnancy, the obstetrician should rely on fetal sex in combination with the number of placentas, and characteristics of the dividing membrane.

• [Clinical significance of echogenic amniotic fluid at term pregnancy]

  Authors: Witold Malinowski

  Ginekologia polska. 03/2002; 73(2):120-3.

  PURPOSE: This study is aimed to determine the clinical significance of echogenic amniotic fluid. MATERIAL AND METHODS: I surveyed 9 at term pregnancies in which the amniotic fluid was echogenic.PURPOSE: This study is aimed to determine the clinical significance of echogenic amniotic fluid. MATERIAL AND METHODS: I surveyed 9 at term pregnancies in which the amniotic fluid was echogenic. Morphologic characteristics of amniotic fluid were assessed from samples taken at amniocentesis or upon delivery within one day after last sonographic examination. RESULTS: In pregnancies with echogenic amniotic fluid, assessment revealed clear fluid in 4 cases (44.5%), vernix caseosa in 4 (44.5%), and meconium in 1 (11.0%). CONCLUSIONS: Echogenic amniotic fluid on prenatal sonography is not predictive of fetal distress.

• [Twin birth weight discordance and risk of preterm birth].

  Authors: Witold Malinowski, Waldemar Lipiec, Jacek Partyka

  Medycyna wieku rozwojowego. 7(3 Suppl 1):223-7.

  Our purpose was to determine whether birth weight discordance is a risk factor for preterm birth of twins. Maternally linked 1970-2000 Kutno Hospital birth certificates were used to analyzeOur purpose was to determine whether birth weight discordance is a risk factor for preterm birth of twins. Maternally linked 1970-2000 Kutno Hospital birth certificates were used to analyze gestations resulting in live twins. The degree of discordance correlated strongly with risk for live preterm birth but only for discordances > 20%. Twin birth weight discordance has demonstrated to be a risk factor for preterm birth. The effect was found particularly with discordance > 30%.

• [Successful pregnancy in a patient with chronic renal insufficiency treated with repeated hemodialysis].

  Authors: Piotr Koźmiński, Witold Malinowski, Krzysztof Obrebski, Grzegorz Roman

  Medycyna wieku rozwojowego. 7(3 Suppl 1):287-90.

  A case of successful pregnancy in a patient with chronic renal insufficiency is presented. Appropriately conducted conservative treatment with repeated haemodialysis were decisive for successfulA case of successful pregnancy in a patient with chronic renal insufficiency is presented. Appropriately conducted conservative treatment with repeated haemodialysis were decisive for successful outcome of pregnancy.

• [Preterm birth in multiple pregnancy].

  Authors: Witold Malinowski

  Medycyna wieku rozwojowego. 7(3 Suppl 1):85-96.

  The incidence of twin and higher-order multiple gestations has increased significantly over the past 15 years primarily because of the availability and increased use of ovulation-inducing drugs andThe incidence of twin and higher-order multiple gestations has increased significantly over the past 15 years primarily because of the availability and increased use of ovulation-inducing drugs and newly developed assisted reproductive technologies. Physicians now must deal with a previously unknown type of multiple gestation, that is, the iatrogenic multiple pregnancy. The most significant and common complication of multiple pregnancy is preterm labor resulting in preterm delivery. Perinatal morbidity and mortality are affected by gestational age and weight at delivery as well as by the number of fetuses. Patient education, risk assessment, serial cervical evaluation by manual or transvaginal ultrasound examinations, specialized antepartum clinics will be use to prevent preterm birth in multiple gestations.

• [Type of afterbirth and twin birth weight discordance].

  Authors: Sławomir Szymański, Witold Malinowski, Elibieta Ronin-Walknowska

  Medycyna wieku rozwojowego. 14(4):378-83.

  Twin pregnancies are regarded as high risk pregnancies. It results from the possibility of occurrence of numerous complications both like the ones in singleton pregnancies and those characteristicTwin pregnancies are regarded as high risk pregnancies. It results from the possibility of occurrence of numerous complications both like the ones in singleton pregnancies and those characteristic for multiple pregnancy only. The complication occurring exclusively in multiple pregnancies is discordant intrauterine growth of the fetuses. a response to the question if there a relationship between the type of afterbirth and twin birth weight discordance. Material of the research consisted of 186 afterbirths derived from successful twin pregnancies. In the study the following were taken into consideration: evaluation of placenta/placentas types (mono- or dichorionic), place of umbilical cords insertion, and differences concerning birth weight of newborns. The birth weight discordance of less than 10% (l0) in the twins was noted in 52.7% of pregnancies (n=98), discordance of 10-20% (II degree) was observed in 30.1% (n=56), and over 20% (III degree) in 17.2% (n=32). The birth weight discordance of the third degree was observed significantly more often in dichorionic diamniotic pregnancies with fused placentas. The discordance of third degree (>20%) occurred in 38.2% of female-male pairs, in 35.7% of female-female ones and in 24.3% of male-male pairs. In case of coexistence of both normal umbilical cord insertions the birth weight discordance of third degree occurred in 17.8% of pregnancies, in case of co-occurrence of the abnormal insertion with the normal one--in 21.8% of cases, and in case of the two abnormal insertions--in 10.5%. No statistically significant differences were found. There is a relationship between the type of afterbirth and birth weight in twins. The largest birth weight discordance between fetuses occurs in the following cases: in dichorionic pregnancies with fused placental discs, in case of co-existence of abnormal and normal umbilical cord insertions and in female-male pair of twins.