Twenty studies were included in the review. It was unclear what the study designs were or what the total number of participants was.
Brompheniramine (3 cohort studies including 271 exposed and 56,588 unexposed plus 1 observational study with 65 exposed): the results were inconsistent. The observational study and 1 cohort study reported an increased rate in malformation in the exposed women compared to the general population, while 2 cohort studies reported no increase.
Chlorpheniramine (2 case control studies with 1,327 exposed and 1 observational study with over 100 exposed): no significant association was detected.
Triprolidine (2 case control with 628 exposed and 12,718 controls): no significant association was detected.
Dexchlorpheniramine (1 retrospective record linkage with 1,080 exposed): no significant association was detected.
Ethanolamines: there was limited data on the teratotoxicity of carbinoxamine and clemastine.
Diphenhydramine (1 case control, 1 record linkage, 2 retrospective cohorts, and 1 observational study): the results were inconsistent. Two studies reported an increased rate of congenital abnormalities associated with exposure while 3 studies reported no increase.
Tripelennamine (one observational study): there were 6 major/minor congenital malformations out of 100 exposed.
Methdilazine and alimenazine: no rates of malformations were reported.
Promethazine (2 prospective, 1 retrospective cohorts, 3 case-control studies, 1 record linkage): the results were inconsistent. Two prospective and 1 retrospective cohorts, and 3 case-control studies reported no association between exposure and malformation, while 1 record linkage (1,197 exposed) and 1 prospective cohort reported increased malformation rates in those exposed.
Hydroxyzine (3 prospective cohort studies, 1 record linkage): 3 prospective cohort studies detected no association between exposure and malformation, while 1 record linkage study reported the malformation rates in those exposed to be slightly higher than normal (48 out of 828 exposed).
Azatidine and cyproheptadine (one record linkage with 127 and 285 exposed respectively): there were limited data.
Astemizole (1 prospective cohort study): no association was found.
Cefirizine (1 prospective cohort): no association was found, although the confidence limits were wide.
Terfenadine (1 prospective cohort, 1 record linkage and 1 unpublished): no association was reported.
Phenylephrine (1 observational study, 1 retrospective cohort, 3 case-control studies): the results were inconsistent. One observational study and 1 case-control study reported a significant association, while 1 retrospective cohort and 2 case-control studies reported no association.
Phenylpropanolamine (1 observational, 3 case-control, 1 retrospective cohort): the results were inconsistent. One observational and one case-control study reported a positive association, while a retrospective cohort reported no association. One case-control study reported a positive association between exposure and gastroschesis, while 1 case-control reported no such association.
Pseudoephidrine (1 observational study, 2 retrospective cohorts, 2 case-control and one record linkage): the results were inconsistent. One observational study, 2 retrospective cohort studies, one case-control and one record linkage study reported no association, while a recent case-control reported a significant association between exposure and gastroschesis and vascular disruption.
Naphazoline and tetryzoline: there were limited data.
Oxymetazoline and xylometazoline (1 retrospective cohort and 1 case-control study): no association was detected.
Pheniramine (1 observational study with 831 exposed women): no association was reported.
Sodium chromoglycate: no controlled teratogenicity studies were identified. This section reported results for women exposed to beclomethazone.
Immunotherapy (4 arms of 3 studies with 298 exposed and 100,665 controls): 1 study reported no increased malformation rates with allergy densitisation vaccine but a significant increase with specific desentisisation vaccines. Two retrospective cohort studies and 1 observational study reported no association.
Azelastine, fexofenadine, loratadine, acrivastine and mizolastine, antazoline, ketorolac, levocabastine, budesonide, flunisolide, fluticasone proprionate, mometasone, lodoxamide: no epidemiological studies in human pregnancy were identified.