first trimester


Also found in: Dictionary, Thesaurus.
Related to first trimester: second trimester, first trimester pregnancy

first trimester

The first 3 months of pregnancy.
See also: trimester
References in periodicals archive ?
The Centers for Disease Control and Prevention's (CDC) yearly abortion data from the early 1980s onward indicate that the proportion of abortion procedures performed after the first trimester has stayed relatively stable.
However, its draft guidance published in the autumn offered different advice, saying there was no evidence that a small glass of wine a day caused any harm after the first trimester.
a visit intended for the first trimester occurred during the second trimester; see Figure 1 for graphic display of misclassification).
Definition of exposure to an NSAID was a filled prescription for an NSAID in the first trimester.
It is technically challenging during the first trimester.
The inclusion of this marker into first trimester screening may lead to detection rates of 98% for Down syndrome.
Gonorrhea, chlamydia and syphilis: A swab test performed during the first trimester, at up to 12 weeks of gestation.
According to the most recent data, 90 percent of all abortions are performed in the first trimester and 99 percent within twenty weeks, or near the midpoint of the second trimester.
Moreover, reliable determination of fetal gender using ultrasonography cannot be performed in the first trimester, because the development of external genitalia is not complete.
It was not until relatively recently that the focus of prenatal assessment has shifted to the first trimester.
Increasingly, first trimester miscarriage is treated medically, through use of misprostol to cause contractions to evacuate the uterus, or through expectant management, that is, letting the miscarriage take its natural course.
A Food and Drug Administration public health advisory about paroxetine followed in December, describing preliminary results of two other unpublished studies indicating that paroxetine exposure in the first trimester may increase the risk of congenital malformations, particularly cardiac malformations.

Full browser ?