I am not a doctor and each case is special but the Army has laid out some basic guidelines that can be found in AR 40-501. Review these guidelines and discuss them with the Soldier. Her doctor may have additional input. When in doubt err on the side of caution and follow up with medical authority.
Here is the extract: Paragraph 7-9c
(1) Except under unusual circumstances, the Soldier should not be reassigned to overseas commands until pregnancy is terminated. (See AR 614–30 for waiver provisions and for criteria curtailing OCONUS tours.) She may be assigned within CONUS. Medical clearance must be obtained prior to any reassignment.
(2) The Soldier will not receive an assignment to duties where nausea, easy fatigue, or sudden lightheadedness would be hazardous to the Soldier, or others, to include all aviation duty, Classes 1/2/3. (However, there are specific provisions in para 4–13c that allow the aircrew member to request and be granted permission to remain on flight status. ATC personnel may continue ATC duties with approval of the flight surgeon, obstetrician, and ATC supervisor.)
(3) Restrict exposures to military fuels. Pregnant Soldiers must be restricted from assignments involving frequent or routine exposures to fuel vapors or skin exposure to spilled fuel such as fuel handling or otherwise filling military vehicles with fuels such as mogas, JP8, and JP4.
(4) No weapons training in indoor firing ranges due to airborne lead concentrations and bore gas emissions. Firing of weapons is permitted at outdoor sites. (See (11) below, for other weapons training restrictions.) No exposure to organic solvent vapors above permissible levels. (For example, work in ARMS room is permitted if solvents are restricted to 1999 MIL–PRF–680, degreasing solvent.)
(5) No work in the motor pool involving painting, welding, soldering, grinding, and sanding on metal, parts washing, or other duties where the Soldier is routinely exposed to carbon monoxide, diesel exhaust, hazardous chemicals, paints, organic solvent vapors, or metal dusts and fumes (for example, motor vehicle mechanics). It does not apply to pregnant Soldiers who perform preventive maintenance checks and services (PMCS) on military vehicles using impermeable gloves and coveralls, nor does it apply to Soldiers who do work in areas adjacent to the motor pool bay (for example, administrative offices) if the work site is adequately ventilated and industrial hygiene sampling hows carbon monoxide, benzene, organic solvent vapors, metal dusts and fumes do not pose a hazard to pregnant Soldiers. (See (11), below, for PMCS restrictions at 20 weeks of pregnancy.)
(6) The Soldier must avoid excessive vibrations. Excessive vibrations occur in larger ground vehicles (greater than 1 1/4 ton) when the vehicle is driven on unpaved surfaces.
(7) Upon the diagnosis of pregnancy, the Soldier is exempt from regular unit physical fitness training and APFT testing/weight standards for the duration of the pregnancy and 180 days past pregnancy termination. After receiving medical clearance from their health care provider to participate in physical training, commanders will enroll Soldiers who are pregnant or postpartum to take part in the Army Pregnancy/Postpartum Physical Training (PPPT) program, an element of the Army Physical Fitness Training Program, in accordance with AR 350–1, Army Training and Education. The PPPT Program is designed to maintain health and fitness levels of pregnant Soldiers, and successfully integrate postpartum Soldiers back into unit physical fitness training programs with emphasis on achieving the APFT standards in accordance with guidance provided in the Army Physical Fitness Training Program, and meeting height/weight standards in accordance with guidance provided in the Army Weight Control Program. Pregnant and postpartum
Soldiers must be cleared by their health care provider prior to participating in physical fitness training. Once pregnancy has been confirmed, the Soldier is exempt from wearing load bearing equipment (LBE) to include the web belt, individual body armor (IBA) and/or any other additional equipment. Wearing of individual body armor and/or any other additional equipment is not recommended and must be avoided after 14 weeks gestation.
(8) The Soldier is exempt from all immunizations except influenza and tetanus-diphtheria and from exposure to all fetotoxic chemicals noted on the occupational history form. The Soldier is exempt from exposure to chemical warfare
and riot control agents (for example, nuclear, biological, and chemical training) and wearing MOPP gear at any time.
(9) The Soldier may work shifts.
(10) The Soldier must not climb or work on ladders or scaffolding.
(11) At 20 weeks of pregnancy, the Soldier is exempt from standing at parade rest or attention for longer than 15 minutes. The Soldier is exempt from participating in swimming qualifications, drown proofing, field duty, and weapons training. The Soldier must not ride in, perform PMCS on, or drive in vehicles larger than light medium tactical vehicles due to concerns regarding balance and possible hazards from falls.
(12) At 28 weeks of pregnancy, the Soldier must be provided a 15-minute rest period every 2 hours. Her workweek should not exceed 40 hours and the Soldier must not work more than 8 hours in any 1 day. The 8-hour work day does include one hour for physical training (PT) and the hours worked after reporting to work or work call formation, but does not include the PT hygiene time and travel time to and from PT.
e. Performance of duty. A woman who is experiencing a normal pregnancy may continue to perform military duty until delivery. Only those women experiencing unusual and complicated problems (for example, pregnancy-induced hypertension) will be excused from all duty, in which case they may be hospitalized or placed sick in quarters. Medical personnel will assist unit commanders in determining duties.