Psychosomatics 44:84-85, February 2003
© 2003 The Academy of Psychosomatic Medicine
Postnatal Polydipsia
Nigel Bird, M.B.B.S., Brighton, East Sussex, U.K.
TO THE EDITOR: I report the case of a woman who developed psychogenic polydipsia shortly after the birth of her first child.
Case Report
Following an uneventful full-term pregnancy and a 4.5-hour labor culminating in an uncomplicated vaginal delivery at home, Ms. A, a previously well 29-year-old woman, was seen on the fifth day after delivery with a one-day history of a nonspecific flu-like malaise in conjunction with a bitter metallic taste in her mouth, extreme thirst, and uncharacteristic intense anxiety. The bitter taste tended to build up in between breast-feedings, but while she was actually feeding the baby, she experienced a comparatively relaxing "draining-away" sensation radiating down from her face to the rest of her body. She continued breast-feeding for the next 2 weeks in spite of these symptoms, which persisted until her milk supply dwindled.
On the fifth postnatal day, Ms. A was given a small supply of 2-mg diazepam tablets for symptomatic treatment of anxiety. On the 17th postnatal day, the possibility of atypical postnatal depression was considered (although marked anxiety remained the predominant psychological symptom), and she was given amitriptyline, 100 mg at bedtime. However, she found the medication excessively sedating and stopped taking it after two doses.
In view of her persistent thirst and polydipsia, blood and urine samples were taken on the 18th postnatal day at 11:00 a.m., by which time she had already drunk 12 pints of water. An analysis of the blood and urine samples revealed hyponatremia (sodium: 127 mmol/liter) with low plasma and urine osmolalities (262 and 102 mos/kg, respectively), which was compatible with psychogenic polydipsia.
The next day, Ms. A's thirst lessened and her anxiety subsided, but at the same time, her supply of breast milk dwindled, so that after 4 days, her daughter became dehydrated and required admission to a hospital for rehydration with intravenous fluids. Attempted resumption of breast-feeding was unsuccessful, but fortunately Ms. A's daughter has since thrived on formula feedings.
Ms. A had an unremarkable past medical history apart from an appendicectomy at age 9 and a first-trimester miscarriage at age 27. She had no previous psychiatric history and was not taking any medication when her symptoms began. She worked as a teacher and lived with her husband, who was very supportive throughout her illness.
Discussion
A MEDLINE search for "postnatal" and "polydipsia" revealed no previous reports of an association between the two conditions.
It is notable that the patient's symptoms began at about the time her milk came in and continued until her milk supply dwindled, which raises the possibility that endogenous lactogenic hormones (oxytocin and/or prolactin) could have had a significant role in her illness. Other researchers have reported an association between psychiatric symptoms (anxiety, depression, and hostility) and pathological hyperprolactinemia in nonpregnant women, suggesting that prolactin may have a role in the psychopathology of these individuals.1
However, oxytocin and prolactin are also elevated around the time of delivery, when the patient was asymptomatic, and so it is necessary to investigate specific patterns of release in order to establish the feasibility of a relationship between these hormones and her symptoms. Unfortunately, I know of no study in which oxytocin and prolactin levels were measured in the same women before and after delivery, but several studies have examined the levels of these hormones in separate groups of pregnant and breast-feeding women.
The secretion of oxytocin increases at delivery to stimulate uterine muscle contractions during labor. Studies of oxytocin in labor have shown a wide variation in production between patients,2,3 probably in part because of the pulsatile release of the hormone, which creates a potential sampling error. Postnatally, oxytocin levels rise again rapidly in response to suckling (or even the anticipation of suckling) to promote the release of breast milk, reaching higher peak levels than seen in labor,4 remaining elevated during suckling, and then dropping when suckling ceases.
The secretion of prolactin rises in pregnancy under the influence of estradiol and then drops in the 3 weeks after delivery in nonlactating women.5 However, suckling causes an increase in prolactin levels, with a peak at 20–40 minutes and a return to baseline levels after 3–4 hours. The magnitude of this increase shows considerable variation between individuals but can be to levels above those found during pregnancy.4
The patterns of secretion just outlined provide support for the hypothesis that lactogenic hormones (and prolactin in particular) had a role in our patient's illness. Therefore, it seems prudent to advise her to bottle-feed any additional infants from birth in order to minimize the risk of recurrent illness.
REFERENCES
- Fava M, Fava GA, Kellner R, Buckman MT, Lisansky J, Serafini E, DeBesi L, Mastrogiacomo I: Psychosomatic aspects of hyperprolactinemia. Psychother Psychosom 1983; 40:257-262[Medline]
- Sellers SM, Hodgson HT, Mountford LA, Mitchell MD, Anderson AB, Turnbull AC: Is oxytocin involved in parturition? Br J Obstet Gynaecol 1981; 88:725-729[Medline]
- Leake RD, Weiztman RF, Glatz TH, Fisher DA: Plasma oxytocin concentrations in men, nonpregnant women, and pregnant women before and during spontaneous labour. J Clin Endocrinol Metab 1981; 53:730-733[Abstract/Free Full Text]
- McNeilly AS, Robinson ICA, Houston MJ, Howie PW: Release of oxytocin and prolactin in response to suckling. Br Med J (Clin Res Ed) 1983; 286:257-259
- Hendrick V, Altshuler LL, Suri R: Hormonal changes in the postpartum and implications for postpartum depression. Psychosomatics 1998; 39:93-101[Abstract/Free Full Text]
Get information about faster international access.
Privacy Policy
Copyright © 2003
Academy of Psychosomatic Medicine.
All rights reserved.
Home
| Search
| Current Issue
| Past Issues
| Subscribe
| All APPI Journals
| Help
| Contact Us
|
