Twin Pregnancies: In Vitro Fertilization vs. Spontaneously Conceived

Abstract

Objective: To compare the obstetrical and perinatal outcomes of twin pregnancies after IVF-ET with those of twin pregnancies conceived spontaneously. Methods: Two hundred and six cases of IVF-ET twin pregnancies (IVF group) were compared with 229 spontaneously conceived or ovulation induced twin pregnancies (spontaneously conceived group) for obstetrical and perinatal outcomes. All were delivered between July 1994 and February 2002 at Ajou University Hospital. Their clinical records were reviwed. Results: The mean maternal age of IVF group and spontaneously conceived group was 30.7±3.7 years, 28.4±4.0 years and primiparous women were 86.9%, 58.5% (p=0.000). In IVF group and spontaneously conceived group, mean gestational age was 35.0±1.7 weeks, 35.5±2.1 weeks (P=0.000), mean birth weight 2311.4±411.7 gm, 2324.3±447.1 gm (P=0.015), and frequency of birth weight less than 2500 gm 70.6%, 60.3% (p=0.001). In both groups, the frequencies for preterm labor, preeclampsia, intrauterine growth restriction, and birth weight discordancy were 42.2%, 32.3% (p=0.032), 8.3%, 18.3% (p=0.002), 5.3%, 8.7% (p=0.052%), 7.8%, 10.9% (p=0.262), respectively. On the comparison of the chorionicity, monochorion-diamnion was 2.0%, 36.3% (p=0.000) and dichorion-diamnion was 98.0%, 62.8% (p=0.000). And there was no significant difference in congenital anomaly, Apgar scores, frequency and duration of neonatal intensive care unit admission. Conclusion: In IVF-ET twin group compared with spontaneously conceived group, there was higher incidence of preterm labor, and low birth weight.

목적 : 체외수정시술에 의한 쌍태 임신과 자연 임신된 쌍태 임신의 산과적 합병증 및 주산기 예후를 알아보고자 하였다. 연구 방법 : 1994년 3월부터 2002년 2월까지 체외수정시술에 의한 쌍태 임신된 산모 206명 (체외수정군)과 자연 임신된 쌍태 임신 산모 229명 (자연군) 등 총 435명을 대상으로 임상적 특징 및 산과적 합병증과 주산기 사망률 등을 비교 조사하였다. 통계처리는 Student's t-test, 2 검정 또는 Fisher's exact test를 시행하였다. P≤0.05인 경우 통계적으로 유의하다고 판정하였다. 결과 : 대상 산모의 연령은 체외수정군과 자연군에서 30.7±3.7세, 28.4±4.0세이었고, 산과력상 초산모는 179명 (86.9%), 134명 (58.5%)이었다 (p=0.000). 체외수정군과 자연군에서 분만시 임신 주수는 각각 35.0±1.7주, 35.5±2.1주 (p=0.000), 신생아 평균 출생 체중은 2311.4±411.7 gm, 2324.3±447.1 gm (p=0.015)이었고, 2,500 gm 미만의 저체중아의 빈도는 각각 70.6%, 60.3%로 유의한 차이를 보였다 (p=0.001). 양 군에서 조기 진통은 42.2%, 32.3% (p=0.032), 전자간증은 8.3%, 18.3% (p=0.002), 자궁내 태아 발육지연은 5.3%, 8.7% (p=0.052), 쌍태아간 체중불일치는 7.8%, 10.9% (p=0.262)의 빈도를 보였다. 융모막성은 이융모막이양막은 98%, 62.8% (p=0.000), 일융모막이양막은 2%, 36.3% (p=0.000)로 양 군간에 유의한 차이를 보였다. 이외에 선천성 기형이나 1분, 5분 아프가치 및 신생아 중환자실 입원 빈도 등은 유의한 차이를 보이지 않았다. 결론 : 자연 임신된 쌍태 임신과 비교하여 체외수정에 의한 쌍태 임신은 조기진통 및 저체중아의 빈도가 높았다.