Among those who reported taking folic acid, less than a quarter took in the first trimester, the time where it has the most beneficial effect on the growing fetus.[27], [28] Among the women who delivered at homes, many were not even aware of the instrument being used to cut the cord, leave alone its safety.
Mean exposure levels during pregnancy were 30.3 µg/m for PM10 and 39.9 µg/m for NO2 [see Supplemental Material, Table S3, for descriptive data on air pollution exposures by trimester and time period before measurement (http://dx.doi.org/10.1289/ehp.1204918]. Pearson correlation coefficients between the different exposure averages varied between 0.25 and 0.93 (data not shown).
Stratified analyses by air conditioner use, season of first trimester, commute time, region, race/ethnicity, maternal age, smoking status, and employment status were performed to evaluate possible effect modification using the traffic metric (maximum traffic within 50 m) with the strongest association with SAB.
For the analysis of stillbirth, the exposure (vaccine during pregnancy or during the trimesters) was time dependent.
Chloroform analyzed as continuous variable (increase of 0.1 μg/d) was also associated with an increase in risk for LBW ORR 1.10, 95% CI 1.01-1.19) for the entire pregnancy, as well as for trimester-specific time windows.
While we think that the first trimester is the time of greatest risk, we still don't know if there is ever a safe point in pregnancy.
In fact, I asked if we could postpone the abortion until the third trimester, by which time my daughter would have been almost fully developed; my doctor pointed out that abortions after 24 weeks were illegal.
Unlike our two first trimester losses, this time our son knew about my pregnancy and was over the moon at the thought of being a big brother.
Danielle, who has straight, light auburn hair that falls past her shoulders, was just starting her third trimester at that time, and seemed more perplexed than angry over what was happening.
Based on age groups, education, place of residence, chronic disease situation, and trimester at the time of the survey, there was not any significant difference with regard to vaccination status (p>0.05).
