Epidemiological study (observational study)

Lifestyle Risk Factors Associated with Threatened Miscarriage: A Case-Control Study epidem.

By: Tan TC, Neo GH, Malhotra R, Allen JC, Lie D, Østbye T

Published in: J Fertil In Vitro IVF Worldw Reprod Med Genet Stem Cell Biol 2014; 2 (2): 100123

Aim of study (acc. to author)

A case-control study was conducted in Singapore to investigate the association of several potentially modifiable maternal lifestyle risk factors (e.g. mobile phone and computer use, smoking, alcohol consumption) with threatened miscarriage.

Further details

Threatened miscarriage was defined as vaginal bleeding between the 5th and 10th completed weeks of gestation.

Endpoint/type of risk estimation

reproductive effects and pregnancy outcomes: threatened miscarriage

Type of risk estimation:

incidence

(odds ratio (OR))

Exposure

- other domestic appliance
- mobile communications
- mobile phone
- personal

Assessment

questionnaire: mobile phone and computer use (hours per day based on the most recent one week)

Exposure groups

Group	Description
Reference group 1	mobile phone use: 0 - < 1 hour/day
Group 2	mobile phone use: ≥ 1 - < 2 hours/day
Group 3	mobile phone use: ≥ 2 hours/day
Reference group 4	computer use: 0 - < 1 hour/day
Group 5	computer use: ≥ 1 - < 4 hours/day
Group 6	computer use: ≥ 4 hours/day

Population

Group:
- women
- children in utero
Observation period: November 2010 - February 2011
Study location: Singapore

Case group

Characteristics: pregnant women between the 5th and 10th completed weeks gestation with threatened miscarriage
Data source: Women's and Children's Hospital in Singapore

Control group

pregnant women recruited in the routine antenatal clinics between the 5th and 10th completed weeks gestation with no history of vaginal bleeding
Selection:
- hospital-based

Study size

	Cases	Controls
Eligible	157	266
Evaluable	154	264

Statistical analysis method:

logistic regression

(adjustment:

age
education
gestational age, ethnicity, BMI, regularity of menstrual cycle, housing type, medical, pregnancy, gynaecological, psychiatric history

)

Results (acc. to author)

An association of threatened miscarriage with computer usage (>4 hours/day: OR 6.03, CI 2.82-12.88), mobile phone use (>1 hour/day: OR 2.94, CI 1.32-6.53), second-hand smoke exposure (OR 2.93, CI 1.32-6.48), and caffeine consumption (OR 2.95, CI 1.57- 5.57) was observed. Fish oil consumption was associated with reduced risk of threatened miscarriage (OR 0.20, CI 0.09-0.42).
The authors concluded that prolonged mobile phone and computer use and fish oil supplementation are potential novel correlates of threatened miscarriage that deserve further study.

Study funded by

not stated/no funding

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