Biomaterial Database

Monoamniotic twinning and zona manipulation: a survey of U.S. IVF centers correlating zona manipulation procedures and high-risk twinning frequency. 1996

R N Slotnick, and J E Ortega

Division of Maternal-Fetal Medicine, Eastern Virginia Medical School, Norfolk 23508, USA.

OBJECTIVE An anonymous survey of IVF centers in the United States was employed to calculate frequencies of multiple gestation, monozygotic multiple gestation, and monoamniotic multiple gestation. Rates for zona-manipulated (ICSI, SUZI, zona drilling, mechanical assisted hatching) and non-manipulated pregnancies were compared. RESULTS From 42 IVF centers in the United States, a total of 143 pregnancies was ascertained from zona-manipulated cycles. A multiple gestation frequency of 16.1% was reported. Five monoamniotic twin gestations were identified: four from manipulated cycles and one from a nonmanipulated cycle. All monoamniotic twin gestations resulted in live births, although three showed significant intrauterine growth discordance and one newborn was diagnosed with the VATER malformation sequence. CONCLUSIONS Monoamniotic multiple gestations may be increased in zona-manipulated cycles. The potential obstetric risks and complications of zona manipulation should be discussed with patients.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008846	Micromanipulation	The performance of dissections, injections, surgery, etc., by the use of micromanipulators (attachments to a microscope) that manipulate tiny instruments.	Micromanipulations
D011247	Pregnancy	The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.	Gestation,Pregnancies
D011272	Pregnancy, Multiple	The condition of carrying two or more FETUSES simultaneously.	Multiple Pregnancy,Multiple Pregnancies,Pregnancies, Multiple
D011795	Surveys and Questionnaires	Collections of data obtained from voluntary subjects. The information usually takes the form of answers to questions, or suggestions.	Community Survey,Nonrespondent,Questionnaire,Questionnaires,Respondent,Survey,Survey Method,Survey Methods,Surveys,Baseline Survey,Community Surveys,Methodology, Survey,Nonrespondents,Questionnaire Design,Randomized Response Technique,Repeated Rounds of Survey,Respondents,Survey Methodology,Baseline Surveys,Design, Questionnaire,Designs, Questionnaire,Methods, Survey,Questionnaire Designs,Questionnaires and Surveys,Randomized Response Techniques,Response Technique, Randomized,Response Techniques, Randomized,Survey, Baseline,Survey, Community,Surveys, Baseline,Surveys, Community,Techniques, Randomized Response
D005260	Female		Females
D005307	Fertilization in Vitro	An assisted reproductive technique that includes the direct handling and manipulation of oocytes and sperm to achieve fertilization in vitro.	Test-Tube Fertilization,Fertilizations in Vitro,In Vitro Fertilization,Test-Tube Babies,Babies, Test-Tube,Baby, Test-Tube,Fertilization, Test-Tube,Fertilizations, Test-Tube,In Vitro Fertilizations,Test Tube Babies,Test Tube Fertilization,Test-Tube Baby,Test-Tube Fertilizations
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000328	Adult	A person having attained full growth or maturity. Adults are of 19 through 44 years of age. For a person between 19 and 24 years of age, YOUNG ADULT is available.	Adults
D014430	Twins, Monozygotic	Two off-spring from the same PREGNANCY. They are from a single fertilized OVUM that split into two EMBRYOS. Such twins are usually genetically identical and of the same sex.	Twins, Identical,Identical Twin,Identical Twins,Monozygotic Twin,Monozygotic Twins,Twin, Identical,Twin, Monozygotic