Please select the eligibility criteria that correspond to the clinical trial below.
Title: The Effect of Antenatal Vitamin D Supplementation on Maternal-fetal Vitamin D Status and Neonatal Immune Function: a Randomized Controlled Trial in Bangladesh
Brief Summary: This study is a randomized placebo-controlled trial of oral weekly vitamin D3 (cholecalciferol) supplementation during the third trimester of pregnancy among women in Dhaka, Bangladesh. The overall goal of the study is to establish whether there is evidence that improving vitamin D status among pregnant women in Bangladesh will enhance the resistance of the infant offspring to infection.

The aims of the study are to assess the effect of supplementation on 1) maternal and infant vitamin D status (based on blood concentrations of a vitamin D metabolite) and, 2) markers of neonatal immune function.


Options:
A: Inclusion Criteria:

* Women aged 18 to \<35 years.
* Current residence in Dhaka at a fixed address
* Plans to have the delivery performed at the Shimantik maternity center, and to stay in Dhaka throughout the pregnancy and for at least one month past the date of delivery.
* Gestational age of 26th to 29th (inclusive), estimated based on the first day of the last menstrual period (LMP).

Exclusion Criteria:

* Use of any dietary supplement containing more than 400 IU/day (10 mcg/day) of vitamin D within the month prior to enrolment, or refusal to stop taking supplemental vitamin D at any dose after enrollment.
* Current use of anti-convulsant or anti-mycobacterial (tuberculosis) medications.
* Severe anemia (hemoglobin concentration \< 70 g/L).
* Complicated medical or obstetric history that may increase the risk of preterm birth or labor/delivery complications, based on self-report or clinical assessment by physician (e.g., cardiovascular disease, uterine hemorrhage, placenta previa, threatened abortion, hypertension, preeclampsia, preterm labor, or multiple gestation).
* Prior history of delivery of an infant with a major congenital anomaly, birth asphyxia, or perinatal death (stillbirth or death within first week of life).
B: Inclusion Criteria:

* Healthy women, age 18 to \< 35 years, who are clients at the Shimantik clinic or friends/relatives of Shimantik clients.
* Current permanent residence in Dhaka at a fixed address, and have plans to stay in Dhaka for at least 4 months.
* Pregnant women: Enrolled between 26th and 30th week of gestation (participants enrolled in 26th week will not start on-study until the 27th week or later), with a normal medical and obstetric history. Gestational age will be estimated based on the first day of the last menstrual period (LMP).
* Informed consent provided after having an opportunity to consult with husband and/or family members.

Exclusion Criteria:

* Current self-reported use of any non-food-based dietary supplements containing vitamin D (i.e., commercial micronutrient pills or capsules containing vitamin D).
* Current use of anti-convulsant or anti-mycobacterial (tuberculosis) medications.
* Severe anemia (hemoglobin concentration \< 70 g/L).
* Hypertension (systolic blood pressure \>= 140 mmHg or diastolic blood pressure \>= 90 mmHg on at least two measurements).
* In pregnant women: previous history of giving birth to an infant with congenital anomalies.
* In non-pregnant women: currently breast-feeding.
C: Inclusion Criteria:

* Personal history of asthma, eczema, allergic rhinitis or a history of asthma, eczema, allergic rhinitis in the biological father of the child
* Gestational age between 10 and 18 weeks at the time of randomization
* Maternal age between 18 and 39 years
* Not a current smoker
* English or Spanish speaking
* Intent to participate for the full 4 years (through Pregnancy and then until the 3rd birthday of the child)

Exclusion Criteria:

* Not meeting inclusion criteria
* Gestational age greater than 18 weeks
* Presence of chronic medical conditions
* Taking vitamin D supplements containing more than 2000 IU/day of vitamin D3
* Multiple gestation pregnancy (twins, triplets)
* Pregnancy achieved by assisted reproduction techniques (e.g., IUI, IVF)
D: Inclusion Criteria:

* Women who are within the ages of 18-45 years
* In good general health
* 12 weeks pregnant (based on last menstrual period)

Exclusion Criteria:

* Mothers with preexisting type I or type II diabetes
* Mothers with preexisting hypertension
* Mothers with preexisting parathyroid disease or uncontrolled thyroid disease
* Mothers with multiple fetuses (e.g., twins, triplets, etc.)

Answer: A