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BackgroundTo compare pregnancy complications and birth outcomes for women experiencing nausea and vomiting in pregnancy, or nausea only, with symptom-free women.MethodsPregnancies from the Norwegian Mother and Child Cohort Study (n = 51 675), a population-based prospective cohort study, were examined. Data on nausea and/or vomiting during gestation and birth outcomes were collected from three questionnaires answered between gestation weeks 15 and 30, and linked with data from the Medical Birth Registry of Norway. Chi-squared tests, one way analysis of variance, multiple linear and logistic regression analyses were used.ResultsWomen with nausea and vomiting (NVP) totalled 17 070 (33 %), while 20 371 (39 %) experienced nausea only (NP), and 14 234 (28 %) were symptom-free (SF). When compared to SF women, NVP and NP women had significantly increased odds for pelvic girdle pain (adjusted odds ratio, aOR, 2.26, 95 % confidence interval, 95 % CI, 2.09–2.43, and aOR 1.90, 95 % CI, 1.76–2.05, respectively) and proteinuria (aOR 1.50, 95 % CI 1.38–1.63, and 1.20, 95 % CI 1.10–1.31, respectively). Women with NVP also had significantly increased odds for high blood pressure (aOR 1.40, 95 % CI 1.17–1.67) and preeclampsia (aOR 1.13, 95 % CI 1.01–1.27). Conversely, the NVP and NP groups had significantly reduced odds for unfavourable birth outcomes such as low birth weight infants (aOR 0.72, 95 % CI 0.60–0.88, and aOR 0.73, 95 % CI 0.60–0.88, respectively) and small for gestational age infants (aOR 0.78, 95 % CI 0.73–0.84, and aOR 0.87, 95 % CI 0.81–0.93, respectively).ConclusionsWe found that women with NVP and NP are more likely to develop pregnancy complications, yet they display mostly favourable delivery and birth outcomes.Electronic supplementary materialThe online version of this article (doi:10.1186/s12884-015-0580-6) contains supplementary material, which is available to authorized users.

BackgroundHyperemesis gravidarum (HG) characterized by excessive nausea and vomiting in early pregnancy, is reported to be associated with increased risks for low birthweight (LBW), preterm birth (PTB), small-for-gestational-age (SGA) and perinatal death. Conflicting results in previous studies underline the necessity to study HG’s potential effect on pregnancy outcomes using large cohorts with valid data on exposure and outcome measures, as well as potential confounders. This study aims to investigate associations between HG and adverse pregnancy outcomes using the Norwegian Mother and Child Cohort Study (MoBa).MethodsAll singleton pregnancies in MoBa from 1998 to 2008 were included. Multivariable regression was used to estimate relative risks, approximated by odds ratios, for PTB, LBW, SGA and perinatal death. Linear regression was applied to assess differences in birthweight and gestational age for children born to women with and without HG. Potential confounders were adjusted for.ResultsAltogether, 814 out of 71,468 women (or 1.1%) had HG. In MoBa HG was not associated with PTB, LBW or SGA. Babies born to women with HG were born on average 1 day earlier than those born to women without HG; (−0.97 day (95% confidence intervals (CI): -1.80 - -0.15). There was no difference in birthweight when maternal weight gain was adjusted for; (23.42 grams (95% CI: -56.71 - 9.86). Babies born by women with HG had lower risk for having Apgar score < 7 after 1 minute (crude odds ratio was 0.64 (95% CI: 0.43 - 0.95)). No differences between the groups for Apgar score < 7 after 5 minutes were observed. Time-point for hospitalisation slightly increased differences in gestational age according to maternal HG status.ConclusionsHG was not associated with adverse pregnancy outcomes. Pregnancies complicated with HG had a slightly shorter gestational length. There was no difference in birth weight according to maternal HG-status. HG was associated with an almost 40% reduced risk for having Apgar score < 7 after 1 minute, but not after 5 minutes. The clinical importance of these statistically significant findings is, however, rather limited.

BackgroundElectronic-health (e-health) provides opportunities for quality improvement of healthcare, but implementation in low and middle income countries is still limited. Our aim was to describe the implementation of a registration (case record form; CRF) for obstetric interventions and childbirth events using e-health in a prospective birth cohort study in Palestine. We also report the completeness and the reliability of the data.MethodsData on maternal and fetal health was collected prospectively for all women admitted to give birth during the period from 1st March 2015 to 31st December 2015 in three governmental hospitals in Gaza and three in the West Bank. Essential indicators were noted in a case registration form (CRF) and subsequently entered into the District Health Information Software 2 (DHIS 2) system. Completeness of registered cases was checked against the monthly hospital birth registries. Reliability (correct information) of DHIS2 registration and entry were checked for 22 selected variables, collected during the first 10 months. In the West Bank, a comparison between our data registration and entry and data obtained from the Ministry of Health patient electronic records was conducted in the three hospitals.ResultsAccording to the hospital birth registries, a total of 34,482 births occurred in the six hospitals during the study period. Data on the mothers and children registered on CRF was almost complete in two hospitals (100% and 99.9%); in the other hospitals the completeness ranged from 72.1% to 98.7%. Eighty birth events were audited for 22 variables in the three hospitals in the West Bank. Out of 1760 registrations in each hospital, the rates of correct data registration ranged from 81% to 93.2% and data entry ranged from 84.5% to 93.1%.ConclusionsThe registered and entered data on birth events in six hospitals was almost complete in five out of six hospitals. The collected data is considered reliable for research purposes.Electronic supplementary materialThe online version of this article (doi:10.1186/s12884-017-1296-6) contains supplementary material, which is available to authorized users.

Objective To investigate primarily the dietary intake, as well as demographics and selected lifestyle factors, of women experiencing nausea and vomiting in pregnancy, nausea only, or women who are symptom free.Design Prospective cohort study.Setting The Norwegian Mother and Child Cohort Study, a population-based pregnancy cohort.Sample Analyses were based on 51 675 Norwegian pregnancies.Methods Dietary intake was assessed by a self-reported food frequency questionnaire answered in the first trimester of pregnancy, as were data regarding nausea and vomiting. Chi-squared tests, one-way analysis of variance, and multiple linear regression were used.Main outcome measures Nausea and vomiting in pregnancy (NVP), gestational weight gain (GWG), and dietary intake.Results We found that 17 070 (33%) women experienced NVP, 20 371 (39%) experienced only nausea, and 14 234 (28%) were symptom free. Women with NVP were younger and heavier at pregnancy onset, with the lowest GWG and highest energy intake during pregnancy, primarily from carbohydrates and added sugars, compared with the other groups (P < 0.001). In multiple linear regression analysis of GWG and group adjusted for body mass index (BMI), gestational length, smoking during pregnancy, and energy intake, a significant interaction was found between BMI and group (P < 0.001). A significant effect of group (P < 0.001) was found in all BMI strata, except among underweight women (P = 0.65).Conclusions Our study suggests that women with NVP are characterised by high intakes of carbohydrates and added sugar, primarily from sugar-containing soft drinks. Whether higher intakes of carbohydrates are a response aimed to alleviate symptoms, or are actually provoking the condition, is not known.